If most developers contribute to open-source projects because they want to, rather than because they're forced to, why do we have the GNU General Public License?

Free Software Foundation

That's the question that hit me last night as I tried to sleep in the shadow of Richard Stallman's MIT. Stallman, of course, originated the GPL, a brilliant way to turn copyright on its head in order to force software to remain open.

I'm not trying to be cute here. Think about it. If you you want to maximize adoption and reuse of your software, why wouldn't you use Apache? Perhaps because you don't like the thought of someone using your free software in a proprietary product?

"I would actually rather nobody use my software than be in a situation where everyone is using my gear, and nobody is admitting it," wrote Zed Shaw, creator of a popular library and Web server for Rails called Mongrel.

Shaw, and perhaps other coders, have turned to the GPL as a way to protect their software from use they deem objectionable. But isn't this precisely what the proprietary software licenses do? The only difference is that the GPL forces code to be open, rather than closed.

Are the two approaches so very different? The effect--blocking undesirable use of one's software--is largely the same.

After 10 years in open source, I'm increasingly of the Apache-licensing persuasion because I'm starting to concur with open-source luminary Eric Raymond that "the GPL is unnecessary...(and) is also a confession of fear and weakness."

And if I'm concerned about protection, then why not simply use a proprietary license--one that doesn't scare opposing legal counsel?

With the Web making open-source licensing largely irrelevant, anyway, it's a good time to evaluate the merits of the two dominant open-source-licensing approaches. For this moment in time, they're essentially equivalent, at least to end users and Web developers, neither of which is required to contribute back derivative works.

Indeed, I believe that one of the primary reasons that Linux, MySQL, Lucene, Hadoop, and other Web-oriented technologies have thrived in the past few years is that they have basically come legal-encumbrance-free.

Would Google have built its server infrastructure with Linux if it had been required to contribute all its software back? Almost certainly not. Yes, it has elected to contribute back to MySQL and others when it was advantageous to do so, but I think that Affero GPL, which translates the GPL's provisions to network-hosted software, would have effectively killed the utility of MySQL, Linux, and other open-source technologies for Web titans like Google, Facebook, and others.

In short, perhaps the best thing that could have happened to open source in the past few years is the increasing relevance of its code due to the decreasing relevance of its licensing. More adoption due to fewer controls.

Developers don't contribute to open-source projects out of force. They do so out of interest, desire for recognition, and other reasons. Once you take force out of the equation, the GPL loses its relevance except as a tool to protect against competition...which proprietary licensing perfected long ago.

For those who worry about the world being closed off behind proprietary licenses, it's not going to happen. The software world has been opening up, though not always at the pace some open-source advocates would prefer. On this point Tim O'Reilly has correctly argued:

If you close things off, eventually, you lose. This is why one of my slogans is, "Create more value than you capture." As long as people are doing that, I don't care whether they're trying to capture some value (through proprietary licensing).

In other words, people don't have to be forced into openness. It happens out of natural, selfish desires. Given the history of humanity, that's probably a more dependable basis for business strategy than an expectation of charitable donations through code contributions.

So, wither the GPL? I'm asking a sincere question to which I have hunches but no definitive answers. I'd love to hear your thoughts.

Disclosure: my company licenses its software under the GPL. This post reflects my personal (evolving) opinion and should not be construed as representative of the intentions of my employer.